I'm still inclined to think that a totally invented Jesus would have met with more opposition than a failed fanatic Jesus.
Are any of the Star Wars characters or Start Trek characters based on any real people?
How many fans follow these characters so AVIDLY?
Why would some Star Wars fans be in fact supporters of Darth Vader in preference to the good heroes?
Why would people go to the extent of learning Clingon (a fictional language) and ADMIRE Clingons?
Why would people spend the time and effort to learn Elvish or Middle Earth geography?
There really is no need to invent a person from scratch, just attach whatever Theological nonsense you like to an already known Preacher and you avoid the problem of people saying that they never even heard of the guy.
A lot of fiction is based upon an AMALGAMATION of FACTORS.
It is a fact that in that era there were SCADS of apocalyptic preachers claiming to be messiahs.
The Jesus myth could be based upon ALL of these charlatans rather than ONE PARTICULAR character.
If I am going to write a story about microbiologists that invent a cure for a contagion

then I might base it on an AMALGAM OF personalities that I might be familiar with directly or even one personality.
However, if I did not know any myself but I am familiar that there are people who do that kind of work I would base my protagonists on the CONCEPT of microbiologists rather than on a particular one actual person who is a microbiologist.
Since the writers of the gospels never met Jesus and since Paul never met Jesus then the only people who told us about Jesus never in fact met any person called Jesus.
So the whole thing is a myth based upon a FICTIONAL EXAMPLE of the PLETHORA of messiah pretenders many of whom may have in fact been crucified. If you know about the Essenes and the Dead Sea Scrolls.... they had a leader who got crucified on a tree.... unfortunately a few decades before the supposed Jesus.
So the whole myth could be the work of a FERTILE mind based on an AMALGAM of mythological traditions and other events but not on a PARTICULAR ONE person..... they are based on the IDEA of a class of persons.
Why go to all of the trouble of saying "Prophets have no honour in their own land", if no one from Galilee was saying, "Yeah, we knew that guy and he was just a crazy son of a carpenter...", if he was a total invention? I mean why bother to account for his unpopularity in a particular region if he was never anywhere at all?
Question..... have you ever taken a class in CREATIVE WRITING?
Do you know how to create a BELIEVABLE and thrilling STORY?
According to your logic…. Hercule Poirot is based on a real character….. how could it be possible for Agatha Christie, an English woman, to make Poirot a Belgian who is always mistaken for French? I mean if she did not really have a real person she was basing the character in her fiction upon then why on earth would this BRITISH lady make her character to be a FOREIGN character. How could a WOMAN know about what it takes to care and pamper a MUSTACHE. How could she be able to describe all these actions Poirot took to wax and net his mustache. What about Hastings? Could he have been a real character too?
Why would Homer make it so that Athena who is a goddess actually dip Achilles in the holy fire and make him impregnable but miss that heel?
Why would Rowling write Harry Potter the hero of her story to be FEEBLE and less intelligent than some half muggle girl wizard? Why would she make Hermione a half muggle if she is so great a witch?
Was there really a Scrooge? Was there really an Oliver Twist? Was there really a Sherlock Holmes?
All of these are FLAWED characters who were described to be within FLAWED worlds and places and with FLAWED actions and experiencing the occasional very MUNDANE occurrences.
If you know about GOOD FICTION WRITING you would know that what it takes to make a story good and believable is to write it based on reality……….but not any PARTICULAR REALITY rather on a CLASS of reality.